1993 Chevrolet Suburban Owner's Manual - Page 280

Thesenumbersonan Energy Conserving II oil container show itsviscosity,or thickness. as SAE 1OW-40 or SAE 2OW-50. Do notuseotherviscosityoilssuch Oils withthesewordsonthecontainerwillhelpyousavefuel. Thisdoughnut-shapedlogo(symbol)isusedonmostoilcontainerstohelp you select the correct oil, You shouldlookforthisonthe displaythelogo. oil container,anduse only those oils that GM Goodwrench@ oil (in Canada,GMEngine for your vehicle. Oil) meetsalltherequirements Engine Oil Addifives: Don'taddanythingtoyouroil. somethingshouldbeadded. YourGM dealer is readytoadvise if you think When to Change Engine Oil: See if any one of these is true for you; Mosttripsarelessthan 4 miles (6 km). It's below freezing outside andmosttripsare less than 10 miles (16 km). Theengineisat low speed most of thetime (as in door to door delivery,orinstop-and-go traffic), You tow a traileroften. Mosttripsarethroughdustyplaces. Thevehicleisfrequentlyoperatedoff-road. I f anyoneofthese is trueforyourvehicle,thenyouneedtochangeyour andfilter every 3,000 miles (5000 km)or 3 months-whichevercomesfirst. oil VehicleswithLightDutyEmissions (8500 GVWRor less). If noneofthem is true, change the oil every 7,500 miles (12 500 km)or 12 months-whichever comes first. Change the filter at the first oil change and at everyother oil change after that. VehicleswithHeavyDutyEmissions (8501 GVWR or more). If noneofthem is true,changethe oil every 6,000 miles (10 000 km) or 12 months-whichevercomesfirst.Changethefilteratthefirst oil change and at everyother oil changeafterthat if mileagedetermineswhenyouchangeyour 6-1 5